What is the best base for a garden room?
Ground screws, concrete pads, a slab or existing paving. It depends on your ground, not on fashion.
On sloping or soft ground, a raised base on ground screws or concrete pads is usually the easier route. The bearers sit level on the supports and air runs under the floor.
A concrete slab suits level, firm ground and is the most digging and the most concrete. It also needs time to cure before you build on it.
Existing paving only works if it is level, sound and properly bedded. Old patio slabs on sand are not a base, they're a hope.
Check before you buy or dig
- Ground screws don't go into solid rock or heavy rubble. A test screw is cheap.
- Clay soils move with the seasons. Pads and slabs there need to be deep enough for local conditions.
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Compare bases in the garden room calculatorA general answer, not a structural design. Local rules, ground and loads decide the final build.